stotzer



July 21, 1925. 1,546,687

R. sTU'rzI-:R

DIRECTION FINDING Filed Nov. 2O 1923 2 Sheets-Sheet l y utnmca: mandan 1 July 2l, 1925 1,546,687

R. STTZER DIRECTION FINDING Filed NovY 20. 1923 2 Sheets-Sheet 2 Y Rihanna; mvwkov.:

m MM

Patented July 2l, 1925.

i'rsn STATES ,PATENT orrics.

RUDOLF STTZEB, OF vWETZLAR, GERMANY.

DIRECTION FINDING.

Application tiled November 20, 1923. Serial No. 675,953.

T all when?, 'it lmuy concern:

lle il. known that. I, RUnonF Sri'rrzmn a citizen of therllepubhc of Germany, residing at lVctzlar, Germany, have invel'lted Im-y sired direction irrespective of its position or can have. its direction maintained independently of-its motion.

The object of the invention is generally' to provide method and apparatus for carrying out this method whereby certain errors which otherwise tend to arise can be obviated.

A further object of the invention is a. method of directing a sighting device or the like or an object connected thereto ac'Y eording to which the sighting device or the `likeis trained on a condensing optical system disposed at a Suitable distance therefrom Y and provided witha measuringscreen or provided with o. scale or measuring screen preferably in the focal plane of its objective, the graduations of this screen corresponding to those of the screen provided for the lens system. Il the telescope objective has the same focal length as the condensing lens system, the graduations of the two screens will he similar but. arranged in opposite senses. They may ou the other hand be arranged in the. same sense, if desired7 but in this case prisms or other suitable devices must he interposed to ell'cct.. a reversal of thelimage. lf the two focal lengths are not thesame, similarly marked graduations on the two screens must be disposed in cor-` responding angular positions.

vGenerally the relation between the gradllatons of the screen connected to the telescope objective and the graduations connected to the condensing system correspond to the relation betweenl the respective focal lengths of both systems, according to the following formulre. Screen of the condens,-

ling system: screen of the telescopic objective z foealdength of the condensing system: focal length of the telescopic objective, or screen of the condensing system: focal length of the condensing system z screen of the telescopic objective: focal length of the telescopic objective.

If the sighting device provided With-1. a

graduated circle instead of a screen, the screen of the condensing system is so related to the focal length of the same system that the graduations of the screen correspond to those of the aduated circle; f. i. both scales are g usted in values of angles. Generally equally marked gradual-ions on both scales should correspond to the same values of angles.- Y

If,'as is often the case, it is only necessary to 'define the direction in one plane, for example a, horizontal plane, it is desirable that the graduations on the measuring screen of t'he condensing optical system should be 'visible at different heights, and to this end the graduation lines nre produced over a considerable portion of the field offview, the graduation markings being repeated' several times along the lines. v

If it is required to define the direction in two planes, e. g. horizontal and Vertical, instead of one plane, the screen must be provided with vboth horizontal and vertical graduation lines.

Preferably the graduation of the condensing lens system ext-ends over a considerable port-ion over a considerable field of Aview so that comparatively large movements of the sighting device can be allowed for. If very large move-ments are likely to occur, the measuring screen Wouldhave to berna inconveniently large. To get over this di. eulty, the. condensing lens system together with its measuring screen may be made rotatable. on its bearer. In this ease itjis preferable to make the sighting device rotatable also. If only one of the two is rotated, the amount of the rotation must be allowed IUS for in the reading. If on the other -hand both are rotated through the saine angle,

nojcorrection will be necessary inthe readings. In this manner it is possible to operate 'through a very wide range of angle, when only asinall measuring screen is employed.

It will generally be convenient-to employ 'by indirect firing.

for the condensing lens system an object-ive,

such for example as a p otographic objecf tive, which provides for a large field of view. On the other hand a smaller range of angle willv often have to be employed for the sighting telescope, owing to the use of an eyepiece. In this case it will not always be convenient. or possible so to adjust the apparatus that a graduation on theineasuring screen of the condensing lens system willbe covered by= the corresponding graduation on the measuring screen of the telescope. This difficulty may lle overcome by initially'adjusting the`apparatus so that' vone graduationvof. the screen connected to the condensing lens system (say S0) is covered 'by any graduationo'f the telescope screen (say 40). The dillercnce (S0 j- 40y 40) between these two readings must t-hen be taken into account in subsequent readjustments of the apparatus. A i

By day the measuring screen of the condensing lens system may be lighted by means of a niirlor and at night frm a suitable source, the rays sent out from this screen being utilized to light the measuring screen in-,the telescope. i

A telescope-sight is preferably connected to the condensing lens system for better adjusting it into the desired direction.

It will be seen that the method according to this invention has particular advantages in its application to indirect gun-lire, where underexisting conditions an auxiliary target or aiming pointv disposed at fairly close' range nuist be. used, with the consequent errors `due to the displacement of .the gun after each shot. f l

lVith these general statements of the ob jects and purposes of my invention I will now proceed to describe the embodiments thereof and the inanner in which my invention' is carried out, and it will be under'- Stood that while I have described what'niay .be considered as a preferable embodiment the conditions under whichthey .are to be;

l apparatus, the sighting device being pro# utilized.

Figure 1 is a section through an improved vided with agraduated circle.

Figure 2 is a section through another lmproved apparatus, th'e sightinr telescope being provided with a graduate screen.

In the const ruction of Figure 1 the sighting device 1 which is shown as consisting` of a fore sight and a back sight` is mounted on a circular scale 2A so as to be rotatable about an axis 3. The circular scale 2 may he formed of or mounted on the instrument to be adjusted. At a suitable distance from the sighting device 1 is disposed van objec- -ti-ve 4 consisting of three lenses, in the focal plane of which is arranged a scale or measuring screen 5. It isassunied that. the direction of the Ainstrument to be adjusted is given by aline passing th'rough .the zero point of the scale 2 and the pivot point 3 (as slibwi'i by the arrow).

Figure 1 shows the apparatus after the' circular scale 2 has moved for any reason,

the correct direction. The original position was such that when the sighting device 1 was trained on the objective 4 it pointed to the. graduation, say, 2O on'the screen 5,

.this reading corresponding to an angle sponding to an inclination q to the optical axis of the obiective 4. The diti'erencelbctween the readings of the two graduations the circular scale 2 is adjusted tothe graduation thus obtained (in this case +50).

The zero direction ofthe circular scale 2 is now again parallel to its orlglnal direc the various parts having been adjusted soigo that the circular scale 2 is again trained in tion and makes an angle (51 with the optical axis of the objective 4. whilst the sightingdevice 1 makes an angle qu, with this optical axis.

Figure 2 shows another construction 'in which a telescope is employed as sighting screen 1 which can be observed by means of -an eye-piece 8. At. a suitable distance from the objective 6 is an objective 9 consisting of Vthree lenses and lia-ving a measuring screen The two 1'30` 10 disposed-in its focal plane. measuring screens 7 and 10 are so graduated tively with the two optical axes.

'ation on the telescope screen 7.

that similarly numbered graduations correspond to equal angular positions. The graduations of the two screens must how-A ever` be numbered in opposite senses, unless suitable means are provided between the two objectives fotr reversing the image. The measuring screen may be illuminated by means of mirror 11 rotatable about an axis lVith this arrangement it will be clear that the optical axes of the two objectives 6 and 9 will he parallel if those portions of the rays from a graduation line on the screen v l0. which lie between the objectives 6 and 9 make equal angles 7' and y, respec- These angles will however be equal when the rays from a'V graduation line en the. screen 10 pass through the similarly numbered line on the telescope screen 7.

l\Vith, this arrangement the. condensing lens system 9 is so arranged that when the telescope is adjusted into the desired di-` rection, a graduation on the. screen 10 is covered by the similarly numbered gradu- If nowthe telescope is moved and it is desired to know whether it is still to be trained in the col'- rect direction, it is l'lecessary to determine whether, when the telescope is trained on to the lens system 9 a graduation of the screen 10 (which need not be identical with the graduation previously chosen) is covered b v the correspondingr graduation of the telescope screen 7. 1f this is the case, the telescope. is still trained into the right direction. Otherwise it must be' adjusted by suitable means until sueh an agreement is obtained.

Figure 4 shows a suitable arrangement of measuring screen or scale. It will be seen that the graduation lilies of the screen 33 are right across the screen and the markings are repeated several times along each line.

If it is required to define the directionl in two planes, e. g., horizontal and vertical, instead of one plane, the screen'must bo provided with both horizontal and vertical graduation lines. In Figure 3 such a screen is illustrated and marked by 32.

The graduation preferably extends over a considerable tleld of view so that comparatively large movements of the sighting device can be allowed for. -If very large movements are' likely to occur, the measuring screen would have vto be madeinconveniently large. To get over this ditiicnlty, the condensing lens system togetherwith its measuring sereen may be made rotatable. In this case it is preferableto make the sighting device rotatabletalso. If only one of the two isrotatable, the amount of the' rotation must be allowed for in the read'V ings. It on the other hand both are rotated wide range of angle, when only a sma l` measuringscreen is employed.

In Figure 5 suc-h an arrangement is illus-'- trated in combination with a gun. ring to this figure a gun-barrel 13 1s provided and suitably mounted so that it can be set up in the desired position by means ofA a wheel 14. To the gun is attached an adjustable holder 15 which carries a telescope-sight. 16. The latter is horizontally rotatable by means of aliandle 17 andicon-- sists of an objective 18, a measuring screen 19 similar as drawn in Figure 3 or 4, and an eye-piece 20. A level 21 of suitable form is tixed on the upper side of he telescopesght. 1c. A

Near before or, if desired, behind or aside the gun isl placed a tripod-stand 22 carryintr a. casing 23 which is horizontally rotata le by means of a handle 24. The casing 23 eixcloses an objective 25, a measuring screen l26 corresponding in ,its graduation to the screen 19. Behind the screen 26 are arranged in a frame 27 a lam 28 and a collecting lens 29 for illuminating the screen 26 at night. The frame 27 is changeable. if desired, with a mirror as drawn in Figure 2. 0n the easing 23 is fixed a telescope sight. 30 for better adjusting' the objective 25 into the direction of the -telescope-,sight 16 mounted on the gun. A level 31 is provided on the telescope-sight 30.

.The relations between theobject-ive 25and the telescope-sight 16 are lexactly the same as illustrated in Figure 2. By setting agun as the object. said in' the description of Figure 2 it is easy to recognize inwhat manner the displacements of ,the gun after a shot has been tired may be compensated vil() by employingthe method and the apparatus f forming the subject of the present invention. Having thus described' my invention, what I claim and desire to secure by Letters Patentvisl 1. In apparatus for directingtan object irrespective ot its position. the combination with a sighting device and means connected to the sighting device for measuring angles, of a condensing optical system disposed at a suitable distance from said object, a screen connected to the condensing system, the graduations of the screen being extended over a'considerable portion ot the ield of view of the condensing system, the focal length of the condensing system being so related to the said screen that the graduations of the latter correspond to those of the said means for measuring angles, anda stationary bearer for the condensing s vstem and its screen.

2. In apparatus for directing an object irrespective of its position, the combination bearer for the condensing system and itsV accessory.

3. In apparatus for directing an object irrespcctiie of its position, the combination with a sighting device and means connected to the sight-ing device for measuring angles, of condon giopt-ical system disposed at a suitable dist-ance from said' object, a screen connected toI the condensing system, the grnduntions of the screen 'being extended over a considerable portion of the field of viewof the condensing system, the 'focal length of the condensing system being so related to the said screen that the graduations of the ln'tter'correspond to those of the said ineens ior measuring angles, a mirror movehly r inted behind said screen for illuminetin the same and a stationary bearer for condensing system and its accessory.

4. In apparatus for direc-ting an object irrespective or its position, the' combination with p. sighting device and means connected to the signting device for measuring angles, of a condensing opt-ical system disposed at e suitable distance from said object, 'a screen connected to the condensing system, the graduetions ot the screen bein extended over a considerable portion of t e field of view of the condensing System, the focal length of the condensing system being so related to the said screen that the graduations of the lat-ter 'correspond to those of' the seid means for measuring angles, markings on said gradini-tions, the-said markings being repeated several times along the grsdnations lines, and a stationarybearer for the condensing system 'and its screen.

5. In apparat-us for directingan object irrespective of its position, the combination with in sighting device ond means connected to the sighting device for n'ieasuring angles, of n condensing optical system disposed at a suitable distance from said object, u.'

screen connected to the condensing system, the graduetions of the. screen being extended over a considerable portion of the field of View ot the condensing system, the focf'rl length of the condensing systembemg so related .to the'said screen that the graduations of the ,letter correspond to those of the Leccese' said means `for measuring angles, a stationury beni-er for the condensing system and its screen, and Inezlns for rotating the said con densing system together with its screen on the bearer.

6. In apparatus for directing an object irrespective of its position in combination a sighting telescope, means connected to the siglrting telescope for measuring angles', s. condensing lens system disposed ata snitable distance from said object, a 'screen connected to the lens system, the graduations of the screen being extended over a considerable portion of the lield of view of the lens system, the focal length of the lens system being so related to the said screen that the gruduations of the latter correspond .i

to those of said means for measuring angles and a stationary bearer for the condensing` system and its screen.

7. In apparatus for directing an object.

irrespective of its position'in combination asighting telescope, means connected to the sighting telescope for measuring angles, a. condensing lens system disposed at a suitable .distance from said object, a screen connected to the lens system, the graduations of the screen being extended over a considcrable portion of the field of View of the lens system, the focal length of the vlens system being so related. to the said screen that the graduations of the latter correspond to those of seid means for measuring angles, a stationary bearer for the lens system and its screen, and means for rotating the said lens system together with its screen on the bearer.

8. In apparatus for directing an object irrespective of its position in combination a sighting telescope, an objective in the sighting telescope, adscreen placed in the focal plane of said objective, the graduations of the screen being extended over a. considerable portion of the field of view of the sighting telescope, e condensing lens system disposed at u Suitable distance from said object, ascreen connected to the lens system, the 'graduations of the screen being extended over a considerable portion of the field of view of the lens system, the focal lengths of the telescope-objective and of the lens system being so related to their respective screens that the graduations of both screens correspond to each other, and a stationary bearer for the lens'system and its screen.

9. In. apparatus for directing an 'object lill) tem disposed ata vsuitable distance from said object, a screen connected to the lens system, the gradnations of the latter screen being extended over a considerable portion of the tield of viciv of the leiis-system, the

foral lengths of the telescope-objective and Aconsi'deiable portion of the field of view of the sighting telescope, means vfor rotating ,said telescope, a condensingr lens system disposed at a' suitable distance from said object, a screen connected to the lens sys- '.tem, vthe graduations of the latter Screen being extended over a considerable portion of the eld of View of the lens system, the

-focal length of the telescope-objective and- `of the lens system beingso .related to Vtheir respective screens` that thegraduations of `both Screens correspond to each other, a

stationary bearer for the lens system and its screen, andmeans for rotating the lens system together with its screen on the v bearei'.

11. In apparatus for direction finding the combination with a gun, of a sighting telescope mounted thereon, 'an objective in the sighting telescope, a screen placed in the focal plane of said objective, means for rotating said telescope, a condensing lens system disposed at a suitable distance from said gun, a sci'een connected to the, lens system, the gradnations of the latter screen being cxteiided'over a considerable portion of the field' of View olt the lens system, the foeal lengths of the teleseopeol` jectivc and of. the lens system being so related to their respective screens that the graduations of both screens correspond'to each other, and astationary. bearer for the lens system and 'its screen. y, i v

12. In apparatus for direction finding the A eombinat ion with a gun, of a sighting telescope mounted thereon, an objective in the sighting telescope, a Screen placed in the focal 'plane' of said objective, means for rotating said telescope, a condensing lens system disposed at a suitable distance l'roiii said gun, a screeiilconnected to the lens sys-k tem, the gradiiations of the latter screen being extended over a considerable portion of the tield of view of the lens system, the

focal lengths of the teleseopc-objective and of the lens system being so related to their respective screens that the graduations of both screens correspond to each othei, a stationary bearei'for the lens system and its screen, and means for rotating the stationary lens system together with its screen on the bearer.

13. In apparatus `for direction finding the combination with a gun,- of a sighting telcscope mounted thereon, an objective in the sighting telescope, a screen placed iii the focal plane of said objective, mean for rotating said telescope, a condensingr lens system disposed at a suitable distance ytrom said gun, a screen connected to the lens system, the graduations of .the latter screen being extended over a considerable portion ot' the eld of View of the lens system, the focal lengths of the telescope-objective and of the lens system being so related to their respective screens that the graduations of both screens correspond to each other, a stationary bearer for the lens system and its screen, means for rotating the lens system together vwith its screen on the bearer, and a sighting device connected to the said lens system,

14. In apparatus for direction. finding, the combination with a gun, of a sighting telescope mounted thereon, an lobjective in the sighting telescope, a screen placed in the focal plane of said objective, the graduations of the screen being extended over a considerableportion of the field of view of the sighting telescope, the graduation mai-le ings being repeated several times along the lines, means for rotating the said telescope, a condensing lens system disposed at a snitable distance from said gun, a screen ,connected to the lens system, thel gradnations of the latter screen being extended over a considerable portion of the tield of view of the lens system, its gradnations markings being repeated several times along the lines, 

